Shield and dowel assembly



Dec. 23, 1941. w. is. GODWIN SHIELD AND DOWEL ASSEMBLY Y Filed Deb 27, 1938 2 Sheets-Sheet 1 Dec. 23, 1941. w. s. GODWIN 2,267,024 SHIELD AND DOWEL ASSEMBLY Filed Dec. 27, 1958 2 Sheets-Sheet 2 Patented Dec. 23, 1941 I UNITED STATES PATENT OFFICE;

SHIELD AND DOWEL ASSEMBLY William S. Godwin, Baltimore, Md.,'assignor to W. S. Godwin Company, Inc., a

Maryland corporation of Application December 27, 1938, Serial No. 247,789

The invention relates to load transfer devicesfor supporting the adjacent edges of the slabs into which concrete pavements, particularly road or highway pavements are divided by transverse and longitudinal joints, the present application being in part a continuation of my co-pending application,- Serial No. 173,785, filed November 10, 1937.

In constructing concrete paving joints, it is necessary to rigidly hold both the load transfer devices and the preformed joint filler to line and grade during the placing and working of the concrete around the joints and, particularly, around the filler and transfer devices. The present invention provides, in addition to other improvements, a rigid removable shield, and a multiple, dowel and dowel support assembly, for this-purpose.

During setting, the concrete shrinks, this makes it necessary that each side of the load transfer assembly be free to move relatively to the concrete slab on the other side'of the joint. Any fastening sufiiciently strong to hold together the two sides of the load transfer device in opposition to thistendency will cause the concrete at the joint to check or crack.

In accordance with the present invention, any and all fastening between the two members of v the load transfer device on the opposite side of the joint which might tend to prevent sliding of the members of each pair ofdowels, one relatively to the other in the direction of the length and transversely to the point is eliminated, and the two sides of the respective load transfer units are, in accordance with the improvement, held in position during the placing of the concrete by a removable shield which also protects the preformed filler during the operation of placing and working the concrete, the provision of this shield being an important feature of the invention.

This device serves to hold the two sides of the I load transfer assembly in close and rigid contact with the joint filler during the concrete casting I operatiomi. e., while the concrete is being placed 4 and worked.

This shield is removed as soon as the concrete is properly placed and before it has set so that thereafter the respective sides or ends of the load transfer device 'on the opposite sides of the joint are free to move in the direction of their length and transversely to the joint, 1. e., in opposite directions relatively to each other as the concrete shrinks and swells.

The shield, as already pointed out, also serves an important function in protecting the relatively soft and partially plastic preformed asphalt or similar filler during the pouring and working of the concrete. As soon as the concrete is placed, the shield isremoved permitting the concrete to occupy the slight space thus left vacant and in due course the joint is sealed with hot asphalt above the filler,

In addition to (1) the shield and (2) the method of assembling the load transfer-device and sealing the joint, the invention includes (3) as an article or manufacture, a complete load transfer and filler assembly-adapted to be shipped in assembled form to be placed on and fastened relatively to the road bed with the filler in the position which it is to occupy in the finished pavement and the shield being placed in its operative ing number of load transfer units, and two supporting bars; which may be of channel or angle iron and of a length equal to the length of the fiber and preferably having. downwardly disposed flanges or'equivalent members to enter the soil and thus prevent displacement of the assembly. The load transfer devices or dowel are supported at their respective ends remote from the joint, on these longitudinal'bars, one being on each side of the joint and beneath the corresponding ends of the dowel. Theouter or remote ends of the dowels are maintained in the desired horizontal alignment by means of uprights or other suitable means connected to the dowels and to the bars respectively. The dowel members are frequently provided with flangesor other engaging means for. the, shield one on eachdowel member, the flanges, or the like, of each dowel are shown on the opposite sides of the filler.

In the accompanying drawings, I have illustrated an assembled concrete road joint transfer device and filler. and I have also shown the shield in connection therewith, the illustration being in accordance with the preferred form of the invention and capable of considerable variation As the shields are removable, there are only a few shields to proportion to the number of joints and the assembled units for purposes of 5 shipment are fastened together by means of a sliding relation.

without departure from the spirit of the invention.

In the drawings:

Fi 1 is a side elevation of the load transfer unit assembly placed on the road-bed ready for the pouring and working of the concrete, the shield being in position to hold the dowel flanges in contact with the opposite sides of the filler and in the desired assembled relation. The shield being broken away at one. end for convenience of illustration.

Fig. 2 is a top plan view of the same.

Fig. 3 is a side elevation of the shield removed.

Fig. 4 is a side elevation of the same looking from the opposite side from that which is nearest the observer in Fig. 3.

Fig. 5 is a perspective view of a modified form of the shield for use with wood and similar filler strip which do not require protection.

Fig. 6 is a sectional elevation taken on and from the line 66 in Fig. 2, looking to the left.

Fig. 7 is a section on the line 1-1 in Fig. 2.

Fig. 8 is a section on the line 88 in Fig. 2, looking to the left in said figure.

Fig. 9 is a. section on the line 99 in Fig. 7, looking in the direction of the arrows.

Fig. 10 is a section on the line l0lfi in said figure looking in the direction of the arrows.

Referring to the drawings by numerals, each of which is used to indicate the same or similar parts in the different figures.

,The construction shown comprises, dowels I, a filler 9, supporting means I2, I4, [5, I6, 1 and shield 20. The type of dowel shown is similar disclosed in my co-pending application, except that the bolt II, and the nut l2 in said application are omitted, the dowels I, or each of them in the preferred form shown,'the details not being essential to the present invention, the said details being claimed in my co-pending' application, which consists of a bar or dowel member 2, which is'preferably a solid rollable bar of recend which permits a suflicient length to enter the socket.

The filler plate or strip 9, is the well known preformed filler of asphalt or the like which is more or less plastic, or it may be of wood or equivalent material in which case the alternative form of the shield is used. In the preferred form of the invention as shown the load transfer assembly which is an article of commerce, as al ready pointed out, also comprises supporting bars l2 and I4, shown as in the form of channel bars with their flanges wdisposed downwardly and adapted to enter the material of the road-bed. These are adapted to be placed on and seated in the road bed as shown in Figs, 6 and 7, these flanges serve to hold the filler and the dowels against displacement during pouring and working the concrete. As assembled, i. e., in the artangular cross section, said section being elon- I gated in avertical direction as best shown in Fig.

10. The dowel I also includes as an essential feature, a second dowel member or socket 3, which in the form shown consists of two bars 4 and 5. which are preferably of rectangular cross section elongated in a vertical direction and of the same thickness laterally as the bar 2. The socket bars I and 5 are shownas placed one over the other with their correspdndingi side surface in the same vertical planes and these bars are connected together by side plates 6 and I welded or otherwise secured to theside surfaces of both bars The welding is indicated as I.

This arrangement provides a socket'proper 8' Both of the dowel members, i. e., the bar 2 and 4 and 5 and extending from one to the other.-

thesocketl, as shown, are provided at the-forward end of the socket 3 adjacent the joint and} on the bar 2 at an intermediate point with laterally projecting flanges I0 and II, respectively. I These aresecured to the socket member 3' and the bar member 2 in any suitable manner, as by welding,or the flange It may be formed by turn-' ing the-ends of plates 1 and 8 to ,the side, i. e., outwardly at rightangles, the latter being the construction shown and the flange Ill being welded directly at its inner edges'to the bar or first dowel member 2 at a distance from its socket 7 the bottom supporting bar.

ticle of commerce as described, each bar or first dowel member 2 isprovided with an upright support l5 which is welded at one end, i. e., its upper end, to the rear end of the bar 2, remote from the joint and at the other end to the supporting bar shown as channel I 2. This upright l5 may be of any suitable type or shape, i. e., an angle iron, or channel bar or any'suitable support for holding the bar 2 or the outter end thereof in the desired relation to the supporting bar l2, i. e., In the construction shown, the socket member 3 is supported on the corresponding bottom supporting bar I 4 by means joint so that they may slide freely, one relatively to the otheras the pavement contracts and .ex pands due to change of temperature and the like.

The preformed filler, or filler strips, or plates 9 are slotted at I! to admit the bars 2.

The load transfer units I, as shown in Figs. 6 and 7 and as thus described are suitably spaced and the assembly includingthe bottom bars l2 and H, a sufficient number of load transfer units l,-and a satisfactory length of preformed filler plate 9, equal in length to the bars l2 and H, are assembled as a single articleof manufacture or article of commerce, the bars 2 being passed .through the slots l1, bringing the flanges l0 and they are placed in the desired positions to be occupied by the corresponding pavement joints and a corresponding shield 20, now to be described is placed in position to protect the filler plate and lock the members 2 and 3 of the dowel load transfer devices I in the assembled frelation with the preformed filler plate 9, as shown in Figs: 6 and 7 held between flanges Ill and .l I,

This shield 20 which as shown in cross section in Figs. 6 and 8, and-in side elevation in Figs.

1, 3 and 4,-is of inverted U shaped cross section,

having two legs, 2| and 22 in the form of depending flanges-or webs, the web 22, as shown, is the.

with each other transversely to longer on account of the excess vertical width of the socket member 3 as compared to bar 2. This particular detail is desirable but not essential. The shield 20 is notched upwardly from the bottom edges of its respective webs or legs 2| and 22 providing a series of upright notches 24 on one side and 25 on the other side, these are open at the bottom edges of the webs or flanges 2| and 22 and, as shown, the notches 24 are relalength of the shield in accordance with the desired spacing of the load transfer unit I.

The aforementioned article of commerce consisting of the described assembly of a series of dowels or load transfer units I, and a correspondin'g length of preformed filler 9, with the botmade without departure from the spirit of the invention, in order that the invention and the manner of constructing, applying, operating, and using the same may be fully understood, the specific terms herein are used descriptively rather than in a limiting sense, the scope of the invention being defined in the claims.

What I claim and desire to secure by Letters Patent is:

1. As an article of commerce, a load transfer assembly for a concrete road joint, comprising a tom supporting bars I2 and I4 and the upright support l5 and I6, being placed in position where the joint is to be formed a member of the shields 20 of length corresponding to the length are Y passed downwardly over .the corresponding filler shield 20 also pass outside of and enclose the flanges l0 and H, whereby the corresponding members of each dowel, i. e. bar 2, and socket 3, of each dowel or load transfer unit I are locked in the desired assembled relation and the assembly being accurately positioned the flanges I l2, l4 of the bars [2 and 14 being forced into the ground to hold the assembly against displacement.

The concrete is then poured and worked to form the slabs and the edges adjacent the joints. The shields 20 are then removed. before the concrete has set which causes the concrete to contact the preformed flller plate 9; and the space between the edges of the concrete above the flller plate is sealed with hot asphalt at 21 in Fig.7.

-The shields are only sufficient in number to provide for the number of assemblies employed in each pouring and for the load transfer unit assemblies which are being set up elsewhere during the pouring operation.

It will be noted that the road-bed 28 is crownedas shown in Fig. 1 mainly for drainage purposes and the filler 9 and shield 20 are'correspondingly staked. The cement pavement 29 being normally series of dowel units, each consisting of a bar member adapted to be seated in the concrete on one side of the joint and a socket member adapted to be seated in the concrete on the other 'side of the joint, both said members being in alignment, the bar entering the socket in sliding relation; a pair of bottom supporting bars extending parallel to the joint beneath the bars and the sockets respectively and adapted to rest on the subgrade, and upright supports secured to said sockets and .bar members remotely. from said joint at the upper ends of said supports, the lower ends of said supports being rigidly secured to said bottom supporting bars whereby the individual bars and sockets are supported from said supporting bars in horizontal position with each dowel bar in alignment with its socket; said assembly also comprising a preformed filler through which the bars extend, the bars and sockets having stop surfaces bearing against said filler plate on its opposite sides, and cover means co-operating with said filler plates and adapted to protect the preformed filler during the pouring and to hold the series of load transfer devices in assembled'relation for pouring; comprising a pair of spaced webs adapted to cover the filler plate from the top downwardly, said shield being apertured to pass the bar and socket members and adapted to take over the flanges and enclose each dowel in assembled relation.

2. The combination in a clamp for a bar and socket dowel to hold the dowel in assembled relation with a preformed filler in the formation of a concrete paving joint, the clamp compris- V ing an elongated member of inverted U shape,

having two legs spaced by a distance slightly in excess of the thickness of the filler and connected at thetop, said legs having spaced openings adapted to admit the dowel bars on one side of the filler and to admit the sockets on the other side of the filler, a plurality of said openings being spaced longitudinally of the joint according to the desired spacingfof thedowels,

the alignment of the sockets and dowels being at right angles to said filler, the bars and sockets being provided each witha plate adapted to bear on the opposite sides of the filler in the assembled position of the dowel, the U shaped member being mounted to straddle the filler and engaging the plates oppositely to the flller, holding the sockets and dowels in their assembled relation during the pouring of the concrete.

-.3. The combination with a seriesof bars and v a series of corresponnding and respectively cooperating sockets, the bars and sockets forming dowels for the joints of concrete roads, the series cally described, and the advantages and method of operation having been fully set forth in connection with the drawings, and in the preamble, it being obvious that various changes can be of bars having supporting and spacing means with which they form'a continuous rigid integral structure, the sockets likewise having supporting and spacing means with which they form a continuous rigid integral structure, the bars having abutments bearing on the filler on one side, the sockets having abutments bearing on the assembly for a concrete road joint, comprising a series of dowel units, each consisting of a bar member adapted to be seated in the concrete on one side of the joint and a socket member adapted to be seated in the concrete on the other side of the joint, both said members being in alignment, the bars entering the sockets in sliding relation; a pair of rigid'bottom supporting bars beneath the outer ends of the bars and sockets respectively, and adapted to rest on'the subgrade, and a rigid upright support for each bar and each socket said uprights having their lower ends rigidly secured to said bottom supporting bars, the upper ends of said uprights being respectively secured to the outer ends of said dowel bars, and said sockets whereby the individual bars and sockets over said bottom supporting bars are supported in horizontal position with each bar in alignment with its socket; said assembly also comprising a preformed filler through which the bars extend, the bars and socketsfeach having a fiat abutment bearing on saidfiller, the bar abutment engaging the filler on one side and the socket abutment engaging it on the other side, the rigid connection of the bottom supporting bars to the dowel bars and sockets and said abutments serving to hold the dowel, bars and sockets respectively in alignment and the respective dowels in parallel and at right angles to the filler.

5. As an article of commerce, a load transfer assembly for a concerte road joint, comprising a series of dowel units, each consisting of a bar member adapted to be seated in the concrete on one side of the joint and a socket member adapted to be seated in the concrete on the other side of the joint, said members being in alignment, the bars entering the sockets in sliding relation; a pair of rigid bottom supporting bars having comprising a preformed filler through which-the bars extend, and means for locating and securing the bars and sockets relatively to the filler.

6. The method of forming expansion joints in concrete pavements whichconsists in providing two preformed rigid constructions, one comprising a set of dowel bar members, and the other construction comprising a set of dowel socket members corresponding to the dowel bar members said members in the respective constructions being equally spaced, each rigid construction having a single bottom support in rigid relation with its said members; combining said two rigid constructions, with said bar and socket members respectively in telescoping relation and a joint filler at the center at right angles to the bars and sockets, the bars extending through'the filler atright angles thereto, placing the supports of each said rigid construction on the subing and spacing means with which they form a downwardly projecting portions to enter the subgrade and located one on each side of the joint and extending parallel to the joint beneath the outerportions of the bars and sockets respectively of the series of dowel units and a rigid upright for each bar and each socket of said dowel unit, said uprights having their lower ends rigidly secured to said bottom supporting bars,

continuous rigid integral structure, said supporting and spacing means in each instance comprising a substantially flat rectilinear bar adapted to rest on the sub-grade, parallel to the joint and having flanges extendingdownwardly from said bar and adapted to enter the sub-grade to prevent displacement of the dowel units in horizontal directions, a filler for said joint and means for locking the dowel units in assembled relation to and with said filler.

8. As an article of manufacture a load transfer assembly for concrete road joint, comprising a series of dowel units extending across the joint at right angles thereto and adapted to be seated in the concrete on opposite sides of the joint and a supporting and spacing member for said dowel units on each side of the joint; each said member being rigidly connected to the dowels on the same side of the joint and being in the form of a rectilinear bar parallel to the joint and having a substantially flat portion of a considerable horizontal extent adapted to rest on the sub-grade, each said bar also having a depending portion adapted to enter the sub-grade and serving to prevent yielding of the dowel units 

